1. Field of the Invention
The present invention relates to a microwave oven comprising a cavity, a door for closing off the cavity and a locking device for locking and/or retaining the door, the locking device comprising a movable locking member which is activated by the movement of the door to assume a locked position and an unlocked position upon closing and opening the door, respectively.
2. Description of the Related Art
Locks for microwave oven doors may be provided in a number of ways. Many types of lock rely upon a locking device fitted with a catch-like locking pawl. A disadvantage with this type of locking device is that the locking pawl always assumes a catched locked position when the door is closed, wherein it is necessary to provide the door with a locking button or handle which must be operated when opening the door in order release the locking pawl, whereupon the door can then be opened. See for example U.S. Pat. No. 3,907,088.
Another possibility is to utilize a rocker device or a balance arm construction as a locking device, see for example U.S. Pat. No. 4,749,835 and SE 9202977-6. The advantage attained with these solutions, in comparison to the locking devices above, is that they admit of simple and direct opening of the door without a lock button or handle being needed. However, a problem with such locking devices utilizing rocker or balance arm constructions can be that in certain cases a secure catched position is not obtained. During normal use of the oven, this is not a disadvantage, but rather an advantage as mentioned above, but certain situations are conceivable when it is desirable that the door has a catch function against direct opening during use of the oven. One such situation, for example, is if an explosion should occur in the oven cavity. This explosion may arise due to a food item, such as baked potatoes for example, being cooked at too high a power and/or for far too long a time. The explosion creates a sudden pressure increase in the form of a pressure wave in the cavity and may result in a very hasty or rapid opening of the door, whereupon fire may then spread from the oven. Ovens undergo safety tests in certain countries against this type of occurence, requirements being set for ovens that the door should remain closed and limit any fire present to the oven cavity.